In the 1960s and 1970s the government "hired" a lot of people

Basically, in the 1960s and 1970s there were a lot of unanswered questions still regarding the UFOs like at Roswell and other sites and experiences people had had around the world. So, Like Dr. Hynek was hired by Project Blue Book and the military, many people were "hired" in an undercover way to organizations like NSA whose primary function actually is to understand better what the whole UFO connection is about (But, most people don't know about this).

If you notice in "Project Blue Book" that Dr. Hynek is frustrated a lot in his research by government officials that want to sweep all this information under the carpet for thousands of reasons.

But, if you also notice "The Man in Black" and the "men in Black" in the series wanted Hynek to find out more stuff. So, Project Blue Book government officials were mostly trying to hide the truth whereas the "Men in Black" who contacted Hynek wanted as much true information as possible.

So, many people were hired by the NSA in the 1960s and 1970s who were more intuitive than most people and who also were more intelligent and also survivors and unlikely to have "psychotic Breaks" when exposed to more UFO stuff along the way or who had already been contacted ongoing since they were children by UFO groups and used as Liaisons between Earth and Earth Governments.

What does "Hire" mean?

It mostly means they were protected from harm in order to gather more research ongoing if possible and many of those who successfully brought in more useful information are still alive today in thousands of locations around the world.

So, some of these are working as researchers for groups like NSA and "Men in Black" even today and are still protected from harm as more and more information becomes known worldwide regarding all these issues and more.

The point is to have more in common with groups from different times on earth and also beings from different planets because biologically humans of earth are biologically related to almost all UFOS that visit earth at this point from other planets and also from future and past earth civilizations.